From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stephen Hemminger Subject: Re: [PATCH net-next v6 1/8] vxlan: Restructure vxlan socket apis. Date: Sun, 4 Aug 2013 14:42:15 -0700 Message-ID: <20130804144215.640c9336@nehalam.linuxnetplumber.net> References: <1375382680-3137-1-git-send-email-pshelar@nicira.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org To: Pravin B Shelar Return-path: Received: from mail-pb0-f48.google.com ([209.85.160.48]:39761 "EHLO mail-pb0-f48.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753934Ab3HDVmT (ORCPT ); Sun, 4 Aug 2013 17:42:19 -0400 Received: by mail-pb0-f48.google.com with SMTP id ma3so2589866pbc.21 for ; Sun, 04 Aug 2013 14:42:19 -0700 (PDT) In-Reply-To: <1375382680-3137-1-git-send-email-pshelar@nicira.com> Sender: netdev-owner@vger.kernel.org List-ID: On Thu, 1 Aug 2013 11:44:40 -0700 Pravin B Shelar wrote: > @@ -1642,59 +1651,56 @@ static struct vxlan_sock *vxlan_socket_create(struct net *net, __be16 port) > &vxlan_addr.sin_addr, ntohs(vxlan_addr.sin_port), rc); > sk_release_kernel(sk); > kfree(vs); > - return ERR_PTR(rc); > + return; > } > + atomic_set(&vs->refcnt, 0); > > /* Disable multicast loopback */ > inet_sk(sk)->mc_loop = 0; > + spin_lock(&vn->sock_lock); > + hlist_add_head_rcu(&vs->hlist, vs_head(net, port)); > + spin_unlock(&vn->sock_lock); Overall I am fine with this set, except for this. The change causes a socket to be put into the hash list with a ref count of 0 and then you increment the ref count. If some other thread finds the socket and then decrements the ref count, it would go below zero and might leak, crash or delete it prematurely. This concerns me.